\documentclass{standalone}


    % GRAPHICS
\usepackage{tikz}
\usepackage{pgfplots}
\pgfplotsset{width=7cm,compat=1.3}

\definecolor{green}{RGB}{154,198,30}
\definecolor{blue}{RGB}{0,105,168}
\definecolor{red}{RGB}{217,88,160}


\pgfplotsset{grid style={dashed}}
\begin{document}

\begin{tikzpicture}
%\fill[draw=black,color=red] (6.77,0) rectangle (6.99,6.03);

\pgfplotsset{
    scale only axis,
    %scaled x ticks=base 10:1,
    %xmin=500, xmax=1000
}


\begin{semilogyaxis}[
    legend style={%
        at={(.5,-0.25)},
        anchor=north,
        legend columns=2,
        font=\footnotesize,
    },
  grid=major,
  ymin=10e-5, ymax=1,
  xlabel={PAPR [dB]},
  ylabel={CCDF [-]},
]
    \addplot[color=red,line width=1.3pt]
	table[x=x,y=y]
	{data/papr_16q_o.txt};
\addlegendentry{16QAM OFDM}

    \addplot[color=blue,line width=1.3pt]
	table[x=x,y=y]
	{data/papr_16q_s.txt};
\addlegendentry{16QAM SC-FDM}

    \addplot[color=green,line width=1.3pt]
	table[x=x,y=y]
	{data/papr_qpsk_o.txt};
\addlegendentry{QPSK OFDM}

    \addplot[color=black,line width=1.3pt]
	table[x=x,y=y]
	{data/papr_qpsk_s.txt};
\addlegendentry{QPSK SC-FDM}

%\addplot[mark=none,color=red,line width=1.3pt] coordinates{
%(500,0.867052023121) (1000,0.867052023121)};

\end{semilogyaxis}


\end{tikzpicture}
\end{document}